wateesteeet



(NO Model.)

A. E. STEARNS & s. AQLWATERSTREET.

GHUGK.

No. 363,431. Patented May 24, 1337.

UNITED STATES PATENT OFFICE.

AEVEY E. STEARNS AND STEPHEN A. WATERSTREET, OF AMSTERDAM,

' NEW YORK.

CHUCK.

SPECIFICATION forming part of Letters Patent No. 363,431, dated May 24, 1887.

Application filed June 0, 1886. Serial No. 204,606. (No model.)

To all whom, it may concern.-

Be it known that we, A'LvEY E. STEARNs and STEPHEN A. WATERSTREEI, both citizens of the United States, and residing at Amsterdam, in the county of Montgomery and State of New York, have jointly invented certain new and useful Improvements in Hollow Mandrel- Chucks, of which the following is a specification.

Our invention relates to improvements in hollow mandrel-chucks; and it consists in the devices, parts and combinations of devices and parts, hereinafter particularly described, and specifically set forth in the claims.

The objects of our invention are to produce a chuck which will be simple and strong in its parts and attachments of parts, and be effective for holding bars, rods, or cylindrical pieces of wood or metal intended to be revolved for receiving manipulations. -We attain these objects by the means illustrated in the accompanying drawings, forming a part ofthis specification, in which- Figure 1 represents a hollow mandrel with chuck, with parts broken away, showing the improvements. Fig. 2 is a front end View. Fig. 3 is a cross'sectional view taken at line 1 in Fig. 1. Fig. 4. is a plan view of the elastic clamping devices. Fig. 5 is a side elevation of the same. Fig. 6 is a cross-sectional View taken at line 2 in Fig. 1.

The same letters of reference refer to like parts throughout the several views.

A is a hollow mandrel which is intended to be revolved, and has attached thereto all the parts which operate to produce our improved chuck. The forward end of this mandrel is provided on its periphery with screw-threads a, having a length about equal to twice the length of the screw-thread provided in the clampingnut B. In the forward and screwthreaded portion of this mandrel are made longitudinal slots 6 b--two or more, as may be preferred. The rear ends of these slots terminate with the recesses c, the bottoms of which form seats 0, for the purposes hereinafter pointed out. These slots b and their end recesses, c, are made with a width corresponding with the width of the spring-shanks of the clamping devices or jaws O of the chuck.

The clamping-jaws C of the chuck are in number corresponding with the number of slots 1) in the mandrel, and are each made to be a duplicate of the other. The outer side of each clamping j aw is made with an inclined surface, as shown in Figs. 1 and 5, and have made with themeach a spring-shank, 0, having a width uniform with the width of the jaw. The rear end of each springshank is thickened above the upper line of surface of the main portion thereof, as shown, so as to fill up recess 0' to the line of the outer surface of the mandrel and cause the upper side of the springshank to be on a plane with or slightly below the base of screw-threads a of mandrel A. Made with or fixed to this thickened end of the said shank-which we term the attaching end C"is projection G, which engages with a cor-' responding perforation made in the holdingring D. This holding-ring is made with a bore corresponding with the diameter of the mandrel, and can be moved on the same in either direction It is provided with asetscrew, d, working into a screw-threaded hole in its wall, as shown in Fig. 3, for securing said ring firmly to mandrel A. The perforations d d in thisholdiug-ring are made in number and form and size and place corresponding with projecting pieces or holding devices 0 made with the spring shanks of j aws 0, when in place.

The clam ping-nut B is made with a circular form in one directionand preferably tapering in its forward portion. Its rear end portion is provided with a screw thread, a, corresponding with screw-thread a of the mandrel. Its forwardly-projected portion is made with a conical or tapering form of bore, a, as shown in Fig. 1, the incline of which corresponds with the outer surface incline of jaws O, as shown.

If preferred, the perforations d, in holdingring D and the projections C on the rear end of the spring-shanks of the clamping-jaws, may be dispensed with, and screws passing through the holding end G of the shanks and screwing into the metal of seat 0 may be employed for holding the jaws from being pulled forward.

By our above-described improvements the chuck will be strong in all its parts, and the jaws will be strongly re-enforced from side movement by means of the walls of slots 1) in the mandrel bearing against the side edges of the springshank C, while at the same time the jaws will have a strong attachment with the mandrel.

It is intended to employ this mandrel-chuck for holding broom-handles while the brush is being applied, and for holding cylindrical pieces of wood to be turned in forms, and for holding bars or rods of metal or tubes which are to be worked when being revolved.

The simple screwing of the clamping-nut B on the mandrel toward the holding-ring D will tighten the jaws of the chuck, and a reverse movement of this nut will loosen the same.

Having described our invention, what we claim, and desire to secure by Letters Patent, 1S

1. The combination, with the hollow mandrel A, provided with two or more longitudinal recesses, l), and clamping-jaws 0, having their shanks arranged in said recesses and provided each with a holding projection, 0 of holding-ring D, securely fixed from moving on the periphery of said mandrel, and the perforations d, which receive the holding projections made with said shanks of said jaws, whereby said clamping-jaws will be held from moving longitudinally when operated, substantially as and for the purposes set forth.

2. The combination, with the hollow mandrel provided with screw-threads a, and two or more longitudinal recesses, b b, and the clamping-jaws 0, two or more having beveled outer ends and provided with spring-form shanks, which are arranged within said horizontal recesses of said mandrel and are held from being moved longitudinally by meanssubstantially as described, of the clamping-nut B, provided in the bore of its rearward portion with ascrewthread corresponding with that on the man drel and containingin its forward portion the circular conical form of chamber 12, which contains the beveled clamping-jaws, whereby the said clampingjaws can be at will forced toward each other and at the same time be prevented from movinglongitudinally when about biting on the article being clamped, substantially as and for the purposes set forth.

ALVEY. E. STEARNS. STEPHEN A. WVATERSTREEP. ,witnessesz' JOHN W. EIGHMY, JOHN HEGEMAN. 

